I might have true comfrey, yikes!

Last spring I picked up three comfrey plants from my local garden center. I sort of assumed they were one of the bocking varieties but never got around to emailing the grower to verify. I was looking at my plants yesterday and thinking about chopping them down and where I wanted to put it when I noticed that they are making seeds! According to the tag they are S. grandiflorum which is dwarf comfrey and generally has white, pink or red flowers. These are not dwarf and have the regular purple/blue flowers.

Does anyone know if the sterile varieties make non-viable seeds or do they just not make seeds at all?

If this is true comfrey what kind of germination rate should I expect from all the seed that has apparently already dropped?

This could be interesting... my yard is not big enough for aggressive spreaders...

Sterile varieties make non viable seeds. True varieties make low viability seeds.

Don't try to till it or remove it with a hole and you should be fine. Or say you want it to take over, then it won't;)

Ok, that's fairly reassuring. I think low germination would be ok. I decided to collect a bunch of the seeds and throw them in a pot for a germination test. I didn't count the seeds but I put a small handful in a 6" pot. I'll be interested to see if I get germination and if it's a little higher with fresh seed that what people have been getting from purchased.

Update: I have seedlings! Not too many thankfully. Out of a tablespoon or so of seeds (maybe 200?) I have eight seedlings. They don't seem to grow very fast but I haven't exactly been pampering them either. So far no sign of seedlings on the ground around the parent plants. I'm interested to see if that changes in the spring.